Television system



. w. SOLLER TELEVISION SYSTEM original Filed Jue :50, 19:54

6 Sheets-Sheet 1 INVENTOR.

@n2/CEV, BY

ATTORNEY w. soLLERA 2,243,332

TELEVISION SYSTEM Original Filed June 30, 1934 6 Sheets-Sheet 2 INVENTOR. waffe/v @90au/j g M /l Y 'I a swg 912m@ w dta ATTORNEY R E L L O s W TELEVISION SYSTEM 6 Sheets-Sheet 5 Original Filed Ju ne 30, 1934 mw w W6 .n m A wf May 27, wm. w. soLLER TELEVISION SYSTEM 6 Sheets-Sheet 4 Original Filed Jun 30, 1934 INVENTOR. waffe/rf nf/few) BY Y ATTORNEY m ma@ w May'z', 1941- w. soLLER 2,241332 TELEVISION SYSTEM Original Filed June 50, 1934 6 Sheets-Sheet 5 IN VEN TOR.

l Wam/v @Sn/@Wl A' BY www* May 27, "i941,

W. SOLLER TELEVISION SYSTEM Original Filed June 50, 1934 6 Sheets-Sheet 6 IN VEN TOR. QX/,QXM/ 30K/5w) BY Q A TTORN EY Patented May 27, 1941 TELEVISION SYSTEM Walter Soiler, Cincinnati, Ohio, half to William H. Woodin,

assigner of one- Jr., Tucson, Ariz.

Application June 30, 1934, Serial No. 733,306 Renewed December 9, 1933 (Cl. 178-6.S)

l0 Claims.

My invention relates broadly to television systems and more particularly to a system for the transmission and reception of variations in light intensity by modulated signal energy.

My invention is directed to a complete television system capable of transmitting any stage performance, sports event, news feature, or the like, throughout the country, and receiving and reproducing the scene in any place having reproducing apparatus of the character hereinafter described. The system of my invention can be applied to any scene which can be photographed by a moving picture camera, and provides in place of recording films, two photo-electric retinas which transform the scene into electric current, which may be retransformed into a representation of the scene in every place having reproducing apparatus.

One of the objects of my invention is to provide in the transmission end of a television system means for transformingT rapidly changing scenes into rapidly changing audio frequency currents which can be amplified in the ordinary Way and sent over Wires or broadcasted on a single radio frequency carrier.

Another object of my invention is to provide a television system adaptable for the dissemination of picture current over regular equipment noW in use, that any national broadcasting system,

telephone equipment, or short or long wave length v radio transmitters, or any apparatus that accommodates electrical energy of audible frequency.

Still another object of my invention is to provide a system for receiving television signaling energy in which amplifying and iiltering apparatus of high fidelity characteristics may be located in a number of sub-stations With only a simple forni transiating device required for connection to a distribution system emanating from the substations for use in the home or reproducing location.

A further object of my invention is to provide a lens and mirror system for obtaining a pair of duplicate images for energizing a pair of photosensitive retinas to effect a push-push operation in the input circuit of a transmitter in a television system.

A still further object of my invention is to provide a system for utilizing a rectangular shaped element as a unit in scanning the Whole of an object by reciprocative movement.

Another object of my invention is to provide a construction of alternator for generation of a plurality of different frequency currents for use as carriers and another current of a frequency suitable for operating a scanning system.

Still another object of my invention is to provide a construction of photo-sensitive retina for cooperation with uni-directional scanning.

A further object of my invention is to provide an efficient iiiter system at the receiving end of a television system for selectively isolating the several diiierent frequency currents received from the television transmitter for producing an image at the receiver.

A still further object of my invention is to provide a self-contained, structurally fixed, translating device for rectifying the separate frequency modulated currents and utilizing the uctuatlng currents thus obtained to synthesize the picture elements; to further utilize the unmodulated scanning frequency to control the movement of the scanning unit in synchronism with the shutter in the transmitting apparatus; and to translate the iiuctuating currents obtained after rectiiication of the frequency modulated currents into fluctuating sources of light for reproducing an image.

A further object of my invention is to provide in the translating device at the receiving end of the television system, cathode, grid, and anode electrodes constituting the rectifying elements therein, the anode electrodes constituting also, sources of secondary electron emission and having in relation thereto formative anodes and deflecting plates to form and direct, respectively, point sources of cathode rays onto a fluorescent screen for eiiecting the reproduction of an image.

Other and further objects of my invention reside in the method of television transmission and reception and the apparatus and arrangements as disclosed more fully in the specification hereinafter following and set forth in the accompanying drawings, in which:

Figure 1 is a diagrammatic illustration of the television system of my invention showing the arrangement of the parts of the transmitter and receiver in a radio broadcasting system; Fig. 2 diagrammatically illustrates the system of my invention employed in television transmission and reception over line Wires; Fig. 3 shows an arrangement of multiple receiving circuits for a television receiving system; Fig. 4 is a schematic diagram of the electrical connections in the transmitter of my invention; Fig. 5 is a vertical longitudinal sectional view through the photoelectric camera of my invention; Fig. 6 is a Vertical cross-sectional vievv of the camera taken on line 5 6 of Fig. 5; Fig. 7 is a detailed sectional view on line 7-1 of Fig. 5; Fig. 8 is a greatly enlarged detail View of a section of one of the photo-sensitive retinas; Fig. 9 is a detailed sectional view on line 5*-9 of Fig. 5; Fig. 10 is a vertical longitudinal View, partly in section and partly in elevation, of the alternator employed to generate'the several frequencies; Fig. 11 is an end View partly in elevation, on line I E and partly in sec-tion on lines A A, B-B, C-C, and D-D of Fig. 10; Fig. 12 is a general elevational view of the assembled alternator; Fig. 13 is a detailed enlarged sectional view of one of the stator units taken on line I3I3 of Fig. 10; Fig. 14 is a detailed sectional view on line Ill-14 of Fig. 10; Fig. 15 is a schematic diagram of the electrical connections in the receiving apparatus of my invention; Fig. 16 is a vertical longitudinal sectional View through the picture tube of my invention on line iiiio of Fig. 17; Fig. 17 is a foreshortened horizontal sectional view on line i'l-I1 of Fig. 16; Fig. 18 is a foreshortened sectional side elevation on line i3|8 of Fig. 16; Fig. 19 is an enlarged detail sectional view on line |9`i9 of Fig. 16; Fig. 20 is an enlarged detail plan View of the grid structure of my invention taken on line 20-20 of Fig. 19; and Fig. 21 is an enlarged per..

Vspective'view of the grid structure employed in the picture tube of my invention.

The transmitter The object to be televised is initially referred to a camera in which an image of the object is formed at the position of the shutter. This image is progressively scanned and divided optically into two identical images by means of lens systems and mirrors, as shown by the traces of light rays in Figs. and 6. These two images are focused on two photo-electric retinas, each of which is comprised of a series of photo-sensitive strips shown at i in all figures of the drawings. I indicate in the drawings and throughout the specication, provision for one hundred such strips in each retina, but it is to be noted that more or less may be employed depending on the fineness and size of picture desired. A common anode is provided for each retina; and each strip. together with the common anode, forms a photo-- electric cell. There are right and corresponding icft photo-sensitive retinas having corresponding strips, the connections of which are marked a and a', b and b', etc. Right and corresponding left strips, which are units in the right and left photo-electric retinas, connect to corresponding coils on the same core of an alternator stator. A slit in a shutter exposes the same small area, a rectangular element of the image embracedr by the slit in the shutter, on both right and left unit strips producing current modulations proportional to the light intensity on a small area of each strip. A true modulation proportional to the intensity of light on the small areas is thereby produced by the action of the current through the two areas and the corresponding alternator coils. Corresponding areas on al1 the 100 strips of both left and right retinas are exposed at the same time and similarly true modulations proportional to the intensity of the light on the exposed areas of these strips are produced. Each set of strips connects with coils on different cores of a composite stator and have a different frequency voltage applied to them. The common anodes are connected together, and, therefore, all the alternating currents of different frequencies combine into one complex alternating current passing through a resistance in series with the common anodes and center taps from the alternator coils.

As the slit in the shutter moves across the image, it progressively exposes different areas of the picture to the strips. The frequency of the voltage applied to each strip remains the same, but the light intensity is continually being varied according to the lights and shadows of the picture as the slit moves across the image. The image is thereby transformed into a complex alternating current of 100 or more modulated fundamental frequencies, which current I will call the picture current.

The movement of the shutter across the image in one direction gives one exposure. The shutter is operated through a Scotch yoke mechanism by a synchronous motor supplied with alternating current from a generator driven by the same shaft as the alternator that supplies the voltage for the photo-sensitive strips. The frequency of this source can be 60 cycles, thus giving 120 exposures a second with a shutter system driven by a two pole synchronous motor.

The voltage drop across the series resistance is the input to the first amplifier tube. This must be a very low input tube of the FP-54 type. A portion of the shutter operating current is introduced into the picture current after this rst stage of amplification. If the picture is to be transmitted by radio, the frequencies supplied by the alternator should be kept to within 10,000 cycles so as not to have too large a band. For example, for a 100 strip retina camera, 3900 cycles to 9900 cycles in 60 cycle steps will provide the desired number and range of frequencies. This group of frequencies with continually varying amplitudes, together With a constant amplitude shutter frequency form, in combination, the complex output of the production end of the system. This can be transmitted by wire or by space radio, and it is actually a simpler wave than that being produced by an orchestra which is a relatively complex composition of frequencies.

The alternator is of the inductor type, arranged to produce all the frequencies required and connected to incorporate the push-push feature. As only .extremely small currents are required, this arrangement will be adequate. A separate alternator, also of the inductor type but of larger capacity, for supplying current to the synchronous motor, is mounted on the same shaft.

Figs. 1, 2 and 3 show in block arrangement the units as combined in a number of workable systems. The camera constitutes a source of modulations for the audio frequencies generated in the composite alternator. The output of these two units is a complex audio frequency wave which can be employed to modulate a radio frequency carrier, which, in turn, is amplified and radiates energy, as shown in the left section of Fig. 1. Either long or short waves may be used. The receiver in Fig. 1 comprises the usual selective tuning apparatus and radio frequency rectier or detector, obtaining in the output thereof the complex audio frequency wave. A filter system separates the several frequencies of which those modulated are then conducted to the rectifying section of the picture tube. After rectifying the audio frequency, the former modulation thereof becomes available for control of a source of luminescence at the image screen. The unmodulated frequency is employed to energize deiecting plates for synchronously synthesizing an image of the object initially scanned.

Fig. 2 shows the transmission of the complex audio wave, or picture current, directly over line wires to the filters at the receiving positions. Fig. 2 further shows a distribution system wherein main lters are located in substations and serve a multiplicity of picture tubes. Thus, all that is necessary to receive the images in the home or office is to become a subscriber to this system in much the same manner as telephony is now administered.

Fig. 3 illustrates how the distribution system of Fig. 2 could be applied to the radio receiving apparatus of Fig. l for reception of extremely distant performances, for example, transoceanic events.

Referring in detail to Figs. 4-14 which illustrate the transmitting system, Fig. 4 is a schematic diagram of the circuit arrangement of the apparatus of my invention. Photo-sensitive strips are shown generally at I and I', the common anodes at 2 and 2'. Conductors a, a; h, b; c, c'; etc., show the relation of right and left photo-sensitive strips with coils in the stator of a multiple alternator. These coils designated generally by 3 and 3' have terminals connected to conductors a, a; b, bi'; c, c'; etc., in the pairs, as shown. Coils designated generally by i2 are energized 'oy direct current through leads i3 and provide a magnetic field in the cores, designated generally by 4 I, on which they are mounted together with the respective coils of the series 3, 3'. Alternator 4, which is driven by the shaft which drives the multiple alternator, supplies the power for the synchronous motor 5 which drives the shutter. The center connections from all pairs of coils in the multiple alternator are connected in common to a resistance I5, the other terminal of which connects through battery, or other source of direct current 1, if necessary, to both the anodes 2 and 2'.

Arrows disposed above and below resistance 5 indicates the manner of push-push modulation of the several frequencies. Instantaneous signs of the voltage induced in one of the series of coils 3, 3', are shown -by the -I- and signs adjacent the terminals thereof. nection has a stable potential due to the balancing effect of the voltages at either side of the middle point. The battery 'I has the positive pole thereof connected with the anodes 2, 2', of the photo-electric units, and has a voltage equal to or greater than the peak voltage in the alternator coils 3, 3', so that the anodes are maintained positive with respect to the cathodes of the photoelectric cells at all times. The voltage across the resistance 6 due to the battery 1 may be represented in circuit I by the vector A, indicating the polarity and the magnitude thereof, and in circuit II by vector B; each vector representing the voltage of the battery 1. With instantaneous potentials as indicated, the coil 3 supplies a voltage across resistance 6 as represented by the vector C in circuit I, and coil 3', a voltage represented by vector E in circuit II. As the instantaneous voltages indicated are in the same sense in their respective circuits as the voltage of battery 1, light falling on the photo-electric cells will permit current to now under the force of the sum of the voltages A and C in circuit I, represented -by arrow D, and B and E in circuit II, represented by arrow F. Considering the condition with the phase of the voltages from coils 3, 3', 180 disposed, that is, with the voltages opposite in polarity with respect to the battery 1, the vectors C and E will be reversed, and, under excitation -by light on the photo-electric cells, current will flow in the resistance 6 under the force of the difference between voltages A and C in circuit I, and B and E in circuit II. In either condition, however, the alternating component voltages C and E are in phase and act in pushpush relation, the result being improved modulation by reason of the more definite response and greater signal intensity in the modulated output without sacrice of simplicity and eniciency.

The middle conf envelopes 26 and 26 ductors a, a';

sensitive retina by lens 23 and 23'.

The system may be converted into one wherein the coils 3, 3', supply voltage to the resistance 6 in push-push relation, by a simple rearrangement of the elements disclosed.

The composite `current through the resistance 6 includes the alternating currents from all the coils 3 as separately modulated by the corresponding photo-electricY units. The input to the electron tube 8 is the potential drop across this resistance 6.

Bias potential to cause tube 8 to operate as an amplifier is provided by a battery 9. The output circuit includes transformers Ill and I2; transformer III amplifies and transmits the complex wave comprised of the several modulated different frequencies while transformer I2, the secondary of which is connected in series with that of transformer I, ampliiies and introduces into the output circuit Il! the current which drives the synchronous motor. The frequency of this current is unmodulated and is to be used at the` receiving end to effect synchronism with the scanning at the transmitter.

Fig. 5 is a sectional view through the camera used in the system of my invention. Reference character I5 designates a convex lens which forms an image of the object at the position of the shutter I1. Slit I9 in the shutter I1 permits that portion of t slit to be refocused by lens 20, mirrors 2| and and lens 23 and 23', on the photo-sensitive retinas I and I which are carried by insulating plates 24 and 2d. Light traces shown by dotted lines indicate how these images are formed. Mirrors 2I and 2I' may be replaced by total reflecting prisms to obtain greater delity and eiiciency of reflection and, therefore, a greater intensity of light on each photo-sensitive retina. Anodes 2 and 2' are grill structures of variously spaced elements 2a supported by rods 2b. Rods 25 and 25' support the insulated plates 24 and 24. Glass contain the retinas, I and I', anodes, 2 and 2', and lens 23 and 23' and are exhausted to a high degree of vacuum. Conb, b'; c, c'; etc., connect through terminals on insulating plates 21 and 21' to multiconductor cables 28 and 28'.

Anode connections 29 and 29' are connected to separate terminals on insulating terminal boards 21 and 21'. Insulating covers 3G and Sil' are cemented to glass envelopes v2e and 2t" and support the terminal plates 21 and 21'. Spring members 3I and 3l' fixed to the frame engage grooves 32 and 32' in insulating covers Sil and 30' and with projections 34 from the frame structure serve to keep the glass envelopes 25 and 25' and the associated apparatus in alignment.

Synchronousmotor 35 drives the shutter I1 in reciprocative movement -by means of the Scotch yoke mechanism 33 which consists of channel member 31 fixed to the shutter I1 and roller member 38 operating in the channel member.

Fig. 6 is a sectional View on line 8-6 of Fig. 5 and indicates by the same reference characters, the same elements, as described hereinbefore. Fig. 6 further shows the light traces of a pair of points in the beam of light passed by the slit I9 in shutter I1 from the lens 20 which parallels all rays emanating from the slit I9, through their reflection at points 33 and 33' by mirrors 2i and 2I', and subsequent focus at the photo- Fig. 6 illustrates more clearly the beam character of the scanning element in contrast to the usual ray, by showing the scanning beam bythe dotted line lof yalternator for the `variation of the magnetic `ers 451)', 45o, 45d, etc., serve :cores in fixed spacial relation :are fastened at the ends to i porting strips 59 Fig. rI is a sectional View on line 'l-l of Fig. 5 and further illustrates the relation of scanning beam 39 and photo-sensitive strips i as such that .the beam embraces all the strips simultaneously and, in the scanning progression, continues to embrace all the photo-sensitive strips simultaneously. Fig. '7 also illustrates the structure of the anode 2 and the unequal spacing of the rod elements to secure a minimum of interference for the light rays converging on the retina.

Fig. 8 is an enlarged detail View of the retina I and insulating plate `'i4 'showing the separate, insulated character of the photo-sensitive strips constituting the retina and the individual connection to each strip.

Fig. 9 is a sectional View online 9 9 of Fig. 5 and illustrates the relation of the slit I9 in shutter I'l lto the central opening in the frame structure.

Fig. l is a vertical longitudinal view, foreshortened on both axes, partly in section and partly Ain elevation, of a preferred construction generation of the several frequencies employed in the system of my invention. Reference characters 49a, 4Gb, 40o, etc., designate toothed, laminated iron rotor sections constituting means for Varying the reluctance of the flux paths between the poles of the several laminated U-shapedstator cores, 4m, 4H), 4|c, etc. Magnetizing coils 42a, 42h, 42e, etc., supplied -with direct current produce a magnetic field across the pole pieces of the stator cores 4|a, 4|b, etc., which passes into and out of the rotor sections 40a, 45h, etc., respectively. Thus, as the rotor revolves and the tooth or space portions pass the pole tips, the magnetic field is Varied. By magnetically cutting the wires in coils 3a, 3a; 3b, 35'; etc., mounted on the pole pieces of the stator cores 41a, Mb, etc., this magnetic field generates an alternating voltage in the coils of a frequency depending on the rate of iield. Insulation spac- Vto support the teeth in the laminated rotor sections, to prevent jamming should one of the stator cores become misaligned and to separate the several magnetic fields to prevent interference therebetween.

The various sections are fastened together at different radii by bolts 45, 41 and 48 and supported on shaft 49 which is carried by bearings 50. The sections are secured on shaft 49 between collar I and nut 52 a clamping xture. Washers 53 are provided to prevent injury to the end sections 43m and 40113.

The various stator cores are disposed in a -double conical spiral arrangement around the lrotor as is better shown in Figs.

portingrods 54 carry a number of the stator to the rotor and the side walls 55 at 5S and the transverse members 51 at 58. Supare clamped to rods 54 by members 60 and rivets 6| and serve to brace the rods 54 and to maintain the alignment of stator and rotor elements.

Fixed to the shaft multiple alternator 49 and separate from the assembly, is an individual `generator 4 of somewhat larger proportions, be-

ing of suicient size to supply current to operate 'the synchronous motor to drive the scanning mechanism.

This generator consists of a stator which is tightened to formY 11 and 12. Supl 3.9 in position to embrace all the photo-sensitive strips lv, Aat the same time.

pole structure AG2 mounted yby bracketv 63 to the side wall 55. The rotor member is comprised of a laminated iron section 64 of eccentric shape, for varying the reluctance of the magnetic path between the poles of the stator, and a pair of insulation members 65 fastened on either side of the laminated section 64 to counterbalance the eccentricity of the laminated section. The stator core carries a direct current magnetizing coil 'I3 and generating coils 14 and 14 in which an alternating voltage is induced by the -variations in the magnetic eld due to the rotation of the eccentric laminated rotor element B4, as is more clearly shown in Fig. 14.

Fig. 11 is a side elevation of the multiple alternator on line E-E of Fig. l0 and shows sections on lines A-A, B-B, C-C, and D-D of Fig. 10. The full elevation view on line E-E shows the stepped, concentric arrangement of the rotor sections to provide different linear speeds for the toothed peripheries of the various rotor sections. The section on line A-A shows the disposition of two representative stator cores Mia and 4iq3 in their mutual relation and their relation to the rotor sections, 4513 and g/a. This relation provides on each set of supporting rods 54, a stator core assembly for every fourth rotor section. There are four such sets of supporting rods 54 disposed around the rotor and by proper selection of the initial pairing of stator and rotor elements, each rotor section will be provided with a corresponding stator assembly. This arrangement is more clearly shown in Fig. 12 in which, starting at the right of the illustration, the iirst rotor section has a corresponding stator supported by the upper rods 54, the second section has one supported by the front rods 54, the third has one supported by the lower rods-54, and the fourth has one supported by the Yrear rods 54, not visible in the drawing. The fifth section then will have a corresponding stator assembly supported on the upper rods 54 and so on for the whole of the structure. This separation and distribution insures magnetic distinction and facilitates construction.

The section on line B-B of Fig. 10, shown in Fig. 11, shows the stator core Mai, as representative of the series of stator cores supported on the upper rods 54. This sectional view also shows the mounting of the bracing strip 59 clamped to rods 54 by members 69 to which it is secured by rivets 6|.

The section on line C--C of Fig. l0, shown in Fig. 11, illustrates stator core 4I7c as representative of the series of stator cores supported on the left rods 54, which are the rear rods not visible in Fig. 12.

The section on line D--D of Fig. 10, shown in Fig. 11, shows the stator core 4|a as representative of the cores supported by the lower rods 54. This sectional view also shows the lower transverse member 51 and the mounting of the rods 54 thereon.

The distribution of binding bolts 46, 41 and te isshown in Fig. 11.

Fig. 12 further shows the relation of the generator 4 to the multiple alternator assembly and of saddle straps 6l to which rods 54 are held by rivets 68 and which, in turn, are secured to core die by rivets 69.

Rotor section de having teeth Iii is aligned with the core lile and backed by the insulating spacing member 135e. The teeth are shown to be of an actual width of 1/8, in which case, for the curvature shown, there will be 161 teeth and 161 spaces in the circumference producing 161 cycles of iiuX change per revolution. If this machine is assumed to be rotating at 60 revolutions per second, the frequency generated in the coils Se and 3e will be 60X 161 or 9660 cycles per second which would be suitable as a carrier for light modulations. To facilitate ltering and in order to minimize the band Width required for a transmission system, a difference of 60 cycles between carrier frequencies has been assumed as a workable medium difference. Thus, at 60 revolutions per second of the rotor structure, a difference of one tooth and one space per section will produce the desired difference in frequency of 60 cycles per second. In order to further separate adjacent frequencies and to provide a balanced structure, the sections for adjacent frequencies are disposed on alternate sides of the center section which supplies the highest frequency. Thus, in Fig. 13, adjacentA section 16g provides afrequency diifering by 120 cycles from that provided by section 48e. From the radius d4 at which the teeth in sections 40g and de are aligned, to the radii 6G and 1l, the distance S3 on the circumference indicates the increasing difference which amounts to the width of two teeth and two spaces in the complete circumference.

nator unit. In designatmg the several sections, the alphabetical characters are employed through a to e, ai to e1, a2 to e2, and as to v3, making the total of 1GO sections.

A frequency of 60 cycles per second is chosen for operation of the synchronous motor. Alternator d, shown in section in Fig. 14, is, therefore, provided with a rotor B having one tooth 'Il and onelspace 'i2 producing one cycle per revolution, or 60 cycles per second at 60 revolutions per The synchronous` motor 35 having two poles, similar to the alternator, Will revolve at 60 revolutions per second and effect 120 complete scannings every second which is more than sufficient number to maintain continuous vision. Core structure 62 of the alternator carries direct current magnetizing coil I3 and alternating voltage generating coils 74 and 'I4'.

The receiver The picture current, with the shutter frequency component, is received either by wire or through a broadcast receiver and amplified in the ordinary way. This current is then filtered out into the original frequencies. The current having the shutter operating frequency is amplified separately and provided with an amplitude control. 'Ihe modulated frequencies are applied to a series of grids in the picture tube. 'I'hese grids, together with a series of positively charged strips and a common cathode form a series of ordinary three electrode assemblies grouped together in the picture tube. The series of positively charged strips are electrically connected together and charged at the same potential, but separately associated each with an electrically separate grid.

These three electrode assemblies are operated at cut-off bias so that the currents in the posiand will be the voltages tively charged strips are rectified proportional to the modulations of applied to the grids. The positively charged strips become sources of secondary electron emissions and will produce secondary electrons in proportion to the electrons received from the cathode, the numbers of which are proportional to the light intensities which initiated the modulations. These sources of secondary electron emissions are, in turn, the electron sources for a series of cathode ray units forming the complementary part of the picture tube. Corresponding to each electron source is a guide anode. These guide anodes are electrically connected together and charged at a common higher positive potential than the secondary electron sources. This causes all electron streams, no matter of what intensity, to have the same velocity after leaving the anode. Common deflection plates can, therefore, be used as all of the electron streams will be deflected together. The shutter frequency voltage is applied to the deflection plates to cause these electron streams to deflect in synchronism with the movement of the slit in the camera at the transmitter.

The picture formed on the fluorescent screen as the series of cathode rays deflect back and forth, is changing at the rate of times a second in the example considered. Only a unit strip of the picture, corresponding to the portion the slit in the camera exposes, is produced yat any instant, but this and the complete progressive scanning occur so much faster than the eye can follow that the impression of a complete picture or series of pictures is received by the eye. While the individual pictures do not move, a series of minutely different images will, at the proposed number of 120 a second, be blended into a smoothly moving picture. This result is due to the well known phenomena called persistence of vision.

The secondary electron sources being long thin strips, can receive large numbers of electrons from the cathode and still form point sources of cathode rays by being placed almost in line with the direction through the anode. The sections in the picture tube will be disposed in exactly the same order as the photo-electric strips in the camera to which they are separately responsive.

Various methods of filtering are possible, e. g., some .magnetostriction methods, resistance-caof picture width. Refined filtering and general precision of alignment will also improve the picture.

Fig, 15 is a schematic diagram of the electrical v sion. Anodes 96a,

@i connections in the receiving apparatus of my invention. The input 'i5 to amplifier tube 1B contains the complex audio wave. The output of tube 'it' is further increased in transformer 1'8, the output of which is put through the series of filters ld, lsb, 19e, etc., and filter 89. 'Ihe output of filter Sii is the voltage of synchronizing frequency which is further increased in amplier 3| and transformer S2. Variable resistance 83 controls the amplitude of the synchronizing voltage. Filter 9% comprising a choke coil and condenser further clariiies the synchronizing voltage which is then impressed on the deiiecting plates Sii-i513' in the picture tube 5. The outputs of filters its, '5919, '190, etc., connect to the inputs of the three-electrode assemblies in the rectifying portion of the picture tube S5. The output of nlter lea, as representative of these connections, is shown connected to grid 86d. VA common connection 8l' from one side of each of the filters 19a, lh, 19o, etc.connects to the common cathode 89 which is brought to operating temperature by heater element 99. Source of biasing potential 9| is of such value as to cause the grids Sta., iib, Etc, etc., to operate at cutoff points to effect rectification of the input voltage. Positively charged strips 92a, B2b, 92e, etc., represented by strip $211, in Fig. 15, are electrically connected together and charged at the same potential with respect to the common cathode 89 by source of potential 93. The electrons from cathode 8e, on striking these positively charged strips 92d, 92h, 52e, etc., produce secondary emissions therefrom. Anodes 94a, Sb, 94o, etc., represented by anode 94a in Fig. l5, are more positively charged than strips 92o, 92h, 92o, etc., by source of potential 95 and, therefore, attract the electrons produced in the secondary emisslib, 94o, etc., form the electrons into point sources of electrons or cathode rays and project them as a iiat beam between defiecting plates 84 and 8d' on the fluorescent screen 9G constituting part of the end surface of picture tube 85.

Fig. 16 is a vertical longitudinal sectional view on line Iiii6 of Fig. 1'?, and illustrates the structure which supports the several electrodes in the tube 85 and maintains them in fixed spacial relation. Insulating sheets 9'! of mica or other material of good insulating properties, support the numerous grid assemblies 66 Vand the cathode 89. Transverse rods 98 of conductivematerial support and connect together electrically, the several rst anodes 92. The rods 98 are ired in the side wall of the glass tube 85. The first anode structure provides also for the uniform spacing of the insulating sheets 91 which Yhave slots |99 and |l| to accommodate the rods 98. Secondary anodes 94 are of rectangular tubular cross-section and converging longitudinal section and serve to guide the electrons emitted from the strips 92 into point rays. Supporting rods |92 carry the several anodes 94 and connect them electrically together. The rods |92 are secured in the glass side wall-sas are the rods 93.

Deflecting plates S4 and S are supported in similar manner by rods Connections are made to the several electrodes in conventional manner and led through the glass enevelope of the picture tube 85.

Grounded shield H5 is formed by metallic deposit on the surface of the glass or may be of other suitable form. This tronsfrom the cathode S9 being attracted *di*- |93 and |94 respectively.

shield prevents elecrectly` to anodes 94 instead of through the grids 86: to the first' anodes S2.

Fig. l7vis a foreshortened horizontal sectional view on line of Fig.'16. The disposition of the numerous strip anodes 92' and guide anodes 94 in relation to the insulating spacers 91 and the broad deflecting plate 84, is shown. Deflecting plate 8d is positioned directly beneath plate 84 on the far side of the. electron or cathode beam. Theproportions of the various elements are uniformly somewhat enlarged to clearly show the structure and arrangement thereof. understood Ythat theV nozzle ends anodes e4" are positioned asnear of the guide each other as possible, or otherwisev focused so as toform on the screen 96 a continuous luminous line by the partial blending of distinct adjacent luminous dots. The progression of the luminous line will be a smooth movement due to the smoothly vary-Y ing electric current which promotes the scanning process. Thus, the picture produced will be a; clear reproduction of the scene in the camera range.

Fig. 18 is a foreshortened vertical cross-sectional view on line |8|8 of Fig. 16 and shows the relationy of the common cathode 39 to the individual grids 8B and strip anodes 92,.with the insulating spacers 91 adjustably tting the enclosure by virtue of the foot abutments |95. The grid structures 8Go, 85h, Btc, etc., individual to each section are shown in more detail in Figs. 19, 20and 21.

Fig. 19 is a vertical detail section View on line l9|9 of Fig. 16 and illustrates the alternate positioning ofthe grid structures as supported by adjacent insulating plates 91, in order to provide horizontal alignment of the grid structures with the strip anodes S2 and the cathode 89, but insulated support forY individual electrical connection thereto.Y The vertical displacement between adjacent units has Vno effect on the control function of the grid and needbe no greater than is necessary to aiford sufficient structural strength in the section 91a between the holes IGS which receive the transverse rods lill of the grid structure.

Fig 20 is a further enlarged plan View of the grid structure as seen on line 20--20 in Fig. 19. Transverse rods |01 are lodged in apertures |56 in insulating spacers 91. Longitudinal rod |63 is spot welded to rods |91 at |99, holding rods |01 in spaced relation and serving as a connection terminal. Small size wire y|||l is disposed in spaced turns around the transverse rods it? and fixed thereto at points v| I2.

Fig. 21 .is a perspective View of the assembled grid unit and shows the relation of the members described in connection with Figs. 19 and 20.

The system of my invention is particularly applicable to carrier current line wire operation. The television system of my invention can be practically employed on a large scale through a service company. In the cities, central stations having high grade filters,.and distributing systems similar to the telephone system, may be employed.y Only the picture tubes would be necessary in the subscribers installations, and cables containing fine wire may lead to the units from the central stations. These cables are composites of fine, stranded, enameled Wire as they provide only the small voltage required for excitation of the grids. rie cathode connection is provided through theground. Such a system wouldrequire'a comparatively inexpensiveunit Y vfor the home or office and would allow greater It isY :2,243,132V refinement of filters and associated apparatus.`

The service company plan is practical for dissemination of television entertainment to the general public to whom a multiplicity of controls will always be a source of disappointment, discouragement and general antipathy towards television.

The splitting up of the image into the two images, as provided in my apparatus, is not essential and I may employ a single image falling upon a single photo-electric retina to control the transmission system. The means disclosed herein for obtaining an eXtremelyrapidly changing electron source as is accomplished in the picture tube is a basic phenomena that has many uses and applications other than for television.

While I have shown the preferred form of my invention, I am aware that modications may be made and, accordingly, I desire that it be understood that no limitations upon my invention are intended other than may be imposed by the scope of the appended claims.

What I claim as new and desire to secure by Letters Patent of the United States is as follows:

1. A method of television which consists in simultaneously modulating a plurality of currents of dierent frequencies by the variations of light intensity on a corresponding plurality of points constituting a narrow strip unit portion of an object to be televised, scanning the total object by the progression of said unit portion at a predetermined frequency across said object, combining the said modulated currents of diierent frequencies and current of said scanning frequency to form a complex wave, amplifying and transmitting said complex Wave, ltering the several modulated currents of diierent frequencies and the current of said scanning frequency into separate channels at the receiving end, separately rectifying said ltered modulated currents, utilizing the varying currents resulting from said rectifications separately to control secondary electron emissions, amplifying the voltage of said scanning frequency and utilming said voltage of said scanning frequency to control the deflection of all secondary electrons in synchronism with the progression of said unit strip across said object.

2. In a television system, means for producing a plurality of currents of diiferent frequencies, means for modulating each of said currents by variations in light intensity, means for combining and transmitting said modulated currents, means for separating said modulated currents by virtue of their different frequencies, means for rectifying each of said modulated currents comprising a corresponding plurality of three electrode groups, insulating spacing members disposed between said groups, a common cathode constituting one of the. electrodes, individually insulated grid structures constituting second electrodes, individually coactive anode electrodes constituting third electrodes, a common source of potential connected to said anode electrodes, means for biasing said grid structures with respect to said cathode at cuto potential for effecting rectication of an eX- ternal exciting voltage, means comprising said anode electrodes for producing a plurality o f cathode rays varying in intensity in accordance with the modulations of said rectied voltage, and means for visually translating said cathode rays.

3. In a television system, means for producing a plurality of currents of diierent frequencies, means for modulating each of said currents by variations in light intensity, including means for scanning an object to secure a broader source of modulation, means for combining and transmitting said modulated currents, means for separating said modulated currents by virtue of their diierent frequencies, means for rectifying each of said modulated currents comprising a corresponding plurality of three electrode groups, insulating spacing members disposed between said groups, a common cathode constituting one of the electrodes, individually insulated grid structures constituting second electrodes, individually coactive anode electrodes constituting third electrodes, a common source of potential for said anode electrodes, each of said anode elec-r trodes constituting a source of secondary emission of electrons in proportion to the modulation of the number of electrons received, said anode electrodes angular-ly positioned with respect to said rst and second electrodes, a corresponding plurality of secondary anodes each comprising a tapered tubular member positioned in alignment with the horizontal projection of the emitting surface of the corresponding source of secondary emission, means for shielding said secondary anodes from electrons emanating from said common cathode, transverse rods fixed to each of said secondary anodes and supporting said secondary anodes in spaced relation, a common source of potential connected to said secondary anodes, the tapered tubular formation of said secondary anodes acting to direct said secondary electron emissions into a plurality of cathode rays, a pair of deiiection plates positioned above and below said plurality of cathode rays and embracing all of said rays for controlling the angular movement of said cathode rays in synchronism with said scanning operation, and means for visually translating said cathode rays.

4. A television system comprising a multiplicity of photo-electric units each having an individual photo-sensitive element and an anode common to a plurality of photo-sensitive elements, an alternator assembly generating a plurality of voltages of different frequencies, each generating unit in said alternator including a pair of electromagnetic windings connected in series, the two terminals of said series connection Iconnected to two photo-sensitive elements being Isubjected to light from the same point, a source or potential, a resistance element connected to the negative terminal of' said source of potential, the positive terminal of said source of potential connected to said common anodes, the other terminal of said resistance element connected to the middle connection of said series connected generator coils, an electron tube amplier circuit having input and output circuits, said input circuit connected to the terminals of said resistance element, a transformer, a primary winding of said transformer connected to said output circuit, a synchronous generato-r, a synchronous motor, a second transformer, a series circuit comprising a primary winding of said second transformer, said synchronous motor and said synchronous generator, secondary windings of both of said transformers connected in series circuit, the terminals of said last mentionedseries circuit constituting the output connections for the system converting varied intensities of light into proportional electric currents, and means for translating said proportional electric currents into varying sources of l-ight.

- 5. In a television system, means for obtaining a pair of images, said means comprising a lens and mirror system including a iirst lens acting to form a rst image of an object embraced by the scope oi said rst lens, a shutter having a rectangular shaped aperture disposed for reciprocative movement at the position of said first image, a second lens acting to parallel all rays emanating from the portion of said first image exposed by the aperture in said shutter, a pair of reflecting surfaces disposed in angular relation, the dihedral apex of said surfaces positioned centrally of said second lens parallel to said rectangular aperture in said shutter for permitting each oi said reflecting surfaces to intercept and reflect a portion of the sia-id rays as paralleled by said second lens, a third lens individual to each reflecting member, said third lens acting to focus said reflected parallel rays as second images of said object, a pair of photosensitive retinas positioned at the foci oi said third lenses, said retinas constituting means for conversion of light energy into electric energy, transmitting means, and reception means capable of translating said electric energy into light energy.

6. In a television system,'means for producing a plurality of currents of different frequencies., means for modulating each of said currents by the light yintensity of a separate scanning point, means for scanning an object by a linear scanning element comprising all said scanning points, instrument means for combining said modulated currents, means for separating said currents by virtue of their diiierent frequencies, means for producing a plurality of secondary electron emissions corresponding in intensity to the modulation characteristics of the separate currents, means for forming said plurality of secondary electron emissions into a corresponding plurality of cathode rays, means for delecting all of said rays simultaneously in synchronism with the operation of said scanning means, and means for visually translating said cathode rays.

7. A method of television which consi-sts in simultaneously modulating a plurality of currents oi diiierent frequencies by the light intensity on a corresponding plurality of points constituting a narrow strip unit portion of an object to be televised, scanning the total object by the progression of said unit portion at a predetermined frequency across said object, combining the said modulated currents of different frequencies and current of said scanning frequency to form a complex Wave, ltering the several modulated currents of different frequencies and the current of said scanning frequency into separate channels at the receiving end, producing a plurality of secondaryV electron emissions corresponding in intensity to the modulation characteristics of the separate filtered modulated currents of different frequencies, and deecting all secondary electrons under control of the current of said scanning frequency to simulate the object televised.

8. In a television system, a multiplicity of photoelectric units having photo-sensitive and anode electrodes, means for generating a plurality of voltages of different frequencies including individual center-tapped output circuits for the several voltages, the two end terminals of each output Acircuit being connected to two photosensitive elements subjected to light from the same scanning point, a resistance element connected between said anode electrodes in common the conte aps of said. output circuits in common, currents from all oi said output circuits modulated by the light intensities on the respectively connected photo-sensitive elements being combined in said resistance element, and output terminals connected with said resistance element.

9. A photo-electric receiving system comprising a plurality of frequency selective filter units disposed in series connection, an electron tube amp-liner having the input thereof connected to the output oi one oi said lters; image producing means inducing a common cathode electrode, a corresponding plurality of grid, iirst anode, and second anode electrodes, a kshield element positioned between said cathode and said second anode electrodes, a pair of deflecting plates positioned beyond said second anode electrodes, and a fluorescent screen aligned with said first and second anode electrodes and said ydei-lecting plates; the output of said last mentioned amplier connected to said deiiecting plates, a source of potential, said second anode electrodes connected to the positive terminal of said source of potential, said rst anode electrodes connected to said source of potential at a less positive potential and constituting independent sources of secondary electron emission, the negative terminal of said source of potential connected to said cathode electrode, one terminal of each of the outputs of the others of said lters connected in predetermined order to said grid electrodes, the other terminals of said outputs connected in common to said cathode electrode, and a source of bias potential connected between said common connection and said cathode electrode, the controls eiected by the outputs of said ilters acting to translate 4said modulated electric currentsl into light energy on said iiuorescent screen through the medium of primary electron emission from said cathode and secondary electron emission from ysaid first anode electrodes.

10.1n a television receiving system, image producing means including a cathode electrode providing a primary source of electrons, `a plurality of control electrodes Yassociated with said cathode, a correspondingplurality of anode electrodes associated with said control electrodes and said cathode electrode, said plurality of anode electrodes constituting a plurality of secondary sources of electrons, a corresponding pluralityof secondary anodes associated With said plurality ofY secondary sources of electrons, said secondary anodes acting to form said secondary electrons into a corresponding plurality of point rays, a'pair of deflecting plates embracing all of said point rays of electrons, and operative to deflect all of said rays as a beam of electrons, a 'uorescent screen positioned in the path o said electroni beam and luminescent under the incidence oi said beam, video signals means ior individually varying the charge-s on said control electrodes to control the'primary emission of electrons, and scanning sign-al mea-ns for varying the charges on the delecting plates for controlling the deflection of salid electron beam from the normal position thereof on said fluorescent screen,

W'AL'I'ER SOLLER. 

